Mar.31 (GMM) Jenson Button was all smiles as he lapped up the sun and spoils of victory before jetting to Malaysia, but he admits winning the Australian grand prix is no guarantee of a sound future for Brawn GP.

As he took in a light lunch near the beach with his new girlfriend Jessica at the Stokehouse restaurant near Albert Park, he told reporters he is so excited about the 2009 season that he is having trouble sleeping at nights.

But although reaping the benefits of departed Honda's huge investment last year, the long development path of the BGP001 car, and a power boost in the form of customer Mercedes-Benz engines, 29-year-old Button admits the car's mostly blank livery tells another story.

"We haven't got the budget but, hopefully, we will and hopefully people will take an interest in what we have done with a pretty plain (liveried) car," the Briton is quoted as saying by the UK's Express tabloid.

The much-feted Virgin linkup, estimated by analysts as worth millions of dollars in terms of TV exposure alone in Melbourne, is still just a $500,000 two-race deal, with most of the 2009 budget coming from money pledged by Honda in order to keep the team alive and avoid staff redundancy payouts.

Button, who led a one-two victory for the Brackley camp last Sunday, added: "Our factory and facilities are very good, it is just whether we've enough money to run the machines.

"I am hoping and guessing it is going to be ok. It would be a waste otherwise," said Button.